Population-based estimates of the occurrence of multiple vs first primary basal cell carcinomas in 4 European regions.

Objective: To estimate the population-based incidence of first and multiple basal cell carcinomas (BCCs) throughout Europe.

Design: The registry practices of 4 population-based cancer registries that routinely register BCC incidence were evaluated for inclusion of first and subsequent histologically confirmed BCCs. Where multiple BCCs were not routinely registered, comparisons with hospital databases were made.